Bushing and cylinder reamer



Jan. 10, 1933. J. M. DOLLY BUSHING AND CYLINDER REMER Filed Feb. 24. 195C 2 Sheets-Sheet 2 Patented den. 1G, 1933 earlier oir-rica JAMES M. DOLLY, 0F CHICAGO, ILLINOIS BUSHNG AND CYLINEB REMER .Application filed February 24, i930. Serial No. 430,?56.

rl"his invention relates o a new and improved bushing and cylinder reainer and more particularly to an improved appliance for truing up the cylinders in triple valves andother air-brake appliances which have become slightly worn so as to be considered defective from an air-brake standpoint.

In order to meet the rigid requirements of air-brake apparatus, it is essential that certain internal cylinders be kept uniformly true and properly centered.` The object of this invention is to provide a simple, Veliectivc and easily positioned and operated tool tor performing this adjustment. lt will be apparent as the description proceeds that this tool is also applicable for reaming or grindingprocesses in other types of apparatus than the airbralze mechanism for which it is particularly designed.

Briefly described, the tool comprises a split or expansible cylindrical head adapted tosubstantially litwithin the cylindrical opening that is to be repaired, and provided with a strip of abrasive material wrap ied around the cylindrical surface ot the head so as to engage the inner surface of the cylinder that is to be ground The head is lprovided with internal expansion springs adapted to torce the parts of tl e head apart so as to yieldably t engage the abrasive strip with the inner surface or the cylinder. A removable retaining member is adapted to hold the parts orp the head assembled before it is positioned wit-hin the valve cylinder, atterwhich the retaining. member is removed before the grinding operation talres place. A guide stem projects coaxially from one side of the head, and the stem is journaled in a two-part guide ineinber so formed as to automatically center ituseit within a cylindrical passage that is coaxial with the valve cylinder. ln this manner the tool is automatically held in properly centered or coaxial position within the cylinder Vdu ing the grinding operation. A removable drive shaft is engageable with the opposite side of the grinding head, whereby the head may be rotated either by hand or by a motor.

The principal object of this invention is to provide an improved reamer, sucli as brielly described hereinabove and disclosed more in detail in the specifications which follow.

Another objects is to provide an improved form of expansble grinding head for a valve reamer.

Janother object is to provide an improved torni of centering` guide for the reamer.

Another object is to provide an improved foi-in of detachable retaining member for the expansible head.

Another object is to provide an improvedy torni of detachable driving' spindle for rotating the head.

Other objects and advantages of this invention will be more apparent from the following detailed description of one approved form of apparatus especially designed to carry out the principles of this invention.

ln the accompanying drawings:

Fig. l is a central, longitudinal section i through the assembled reanier in operative position within a triple valve structure.

Fig. 2 is a transverse section, taken substantially on line 2 2 of Fig. l.

F ig. 3 is a longitudinal section through the grinding hea-d, with the retaining member in place, the guide stem being shown in side elevation.`

Fig. a is a perspective view ot the retaining member or spring.

Fig. 5 is a transverse section, taken substantially on the line 5 5 of Fig. 3.

Fig. 6 is a perspective view-of the central segment of the grinding head, with its integral guide stem.

Figs. 7 and 8 are similar perspective views oli the two side segments ot the grinding head.

F ig. 9 is a perspective view of the hollov7 cylindrical member ot' the guide or centering device.

Fig. l() is a side elevation, partially broken' away, of the centering nut otl t-he guide.

rl`his appliance may be considered as consisting ot' three principal parts, the reamer or grinding head, the guiding or centering means therefor, and the detachable drive shaft. The reainer comprises a multi-part cylindrical grinding head, consisting in the example here shown orn a main cent-ral segment l and a pair of similar side segments Cil Sii

2 and 3. The cylinder may be considered as split by a pair oi' substantially parallel planes spaced at equal distances at either side of the axis of the cylinder and parallel thereto. A. pair of guide pins 4 and 5 are formed on or positioned in the cent'al segment 1, so as to project at opposite sides thereof perpendicular to the opposite plane surfaces of the segment, and guide openings 6 and 7 resp ctively are 'formed in the two sic segments 2 and 3 to slidably engage these guide pins 4; and Similar cylindrical openings 8 and 9 are formed through the tivo opposite similar halves of the. p, ient 'l either side of the central avis and perpendicular to the opposite plane Compressed expansion syringe 10 are confined in these chambers 8 and 9. Preferably one of the side segi'nents (for example the segment 3) is formed with extensions il of tiese cylin drical chambers 8 nd 9 so that longer springs 10 may be used. A strip oi a rasive material 12, of substantially the same Width as the reamer head, is positioned for use by inserting one end portion 13 between the central segment 1 and the side segment 2 so that one of the springs 10 will engage this end portion 13 of' the strip and hold it in place. The remainder of the strip is Wrapped around the cylindrical vfall of the head, as best shown in Figs. 2 and 5.

It is essential that the parts of the grinding head be held in assembled relatiton against the action of the springs 10 be'lorc the tool is positioned in the valve cylinder to be ground. For this purpose the retaining spring shown detached in Fig. 4, and in operative position in Fig. 3, is used. rihis retaining sprinfr 1l comprises a pair of parallel end members 15 and 16 connected by a central portion 1T which is preferably curved or looped to one side so as to avoid engagement with the driing spindle, hereinafter described. The outer end faces of the side segments 2 d 3 of the head are provided with similar openings 'for receiving the end portions 15 and 16 of the retaining spring, as best shown in 3. It Will be apparent that as long as the spring 1.4. is in place, the members ol the head will be held in assembled relation with the springs 10 compressed.

A coaxial guide stem 19 is formed integrally with or attacherv to the rear end of the central head segment 1. rl`his stem 19 is adapted to be rotatably journaled within a hollow guide cylinder Q9, shoivn in perspec tive in Fig. 9 and shown in operative position in Fig. 1. One end portion of cylinder 2O is externally threaded at 21 to receive the internally threaded centering nut 2:2. rlhe inner end of nut Q2 is formed with an out Wardly projecting conical surface 23, and an opposit-ely outwardly projecting conical surface Q4 is formed on an integral collar at the end of guide cylinder 20 remote from nut QQ. ln the form ot triple valve apparatus partially indicated in Fig. l, a cylindrical passage in bushing should he 1vith the cylindrical chamber that to be rclnned or ground, which in this e.\'- ample is formed in the bashing QG mounted in the valve structure 2T. lt will now he apparent that if the guide cylinder 2() is inserted through one end oi bushing Q5, that the. conical surface 2l engages with one end of the cylindrical passage inthe bush ing, and the unt is screwed into position on the opposite end oi cylinder 2O so that the conical surface Q3 engages tightly in the opposite end of bn lring the guiding meinber will be properly centered and coaxial within the bnshing Q5. Then the guide stem 19 is inserted rotatably within the guide cylinder 90, the grinding head will be posV ioncd so that its cylindrical grinding s1|rtace is coaxial with the pas-:age in blushingv E. and thc cj/,flindrical chamber in bushing l will then be ground in proper coaxial innen.. n th the passage in bushing Any suitable means may be employed for rotating the reamer or grinding tool. As here shown, the members of the grinding head are hollowed out, as indicated at Q8, and from the inner end of this central ch am ber an internally threaded passage 29 extends eoaxially through central segment 1 and into the guide stem 19. The inner threaded end 30 of a drive shaft 31 is adapted to be detachably threaded into the passage Q9. as shown in Fig. l. The opposite end portion 32 of the drive shaft or spindle is ot suitable noncylindrical form so as to be engaged bya hand Wrench, or motor, or other suitable means for rotating the spindle. In case a driving motor is used, the drive spindle should have a universal joint. as indicated at to compensate for the probable non-alignment of the axes of the reamer and the motor while in operation.

lhen this tool is to be used, the members of the grinding head, and the abrasive strip 12, are assembled, as shown in Figs. 3 and and the retaining member 14; is engaged with the side segments 2 and 3 of the head so as to hold the reamer in this assembled position. The members 2O and 9.2 of the lguide are now positioned in the passage in bushing 25. The grinding tool is now inserted in operative position by pushing the guide stem 19 into the central passage 34 in guide cylinder :20. until the grindingv head is in proper position Within the cylindrical chamber that is to he re-ground. The retaining spring 'lil may non' be removed so that the springs 10 can partially expand and force the segments of tno head apart so as to yieldably engage the abrasive strip with the inner Halls of the valve cylinder. The driving shaft 3l may he engaged Within the grinding tool either hcfore or after the retaining member le is removed, since the central loop 17 of the retaining member `is so formed as to pass around the driving sha t when` in place.V Power is now applied to the grinding shaft 3l and the tool is rotated until the desired surface is ground within the bushing 2G or other cylindrical chamber. The tool may then be removed in an obvious manner.

It will be apparent that a` new abrasive strip 1Q, may be very easily applied whenever necessary, and the other parts of the tool y will last indenitely.

In case the tool were to be used for grinding cylindrical chambers or valve cylinders that do not have to be symmetrical or coaxial with another passage or cylindrical opening, the guide features of this device may be omitted, and the axial length or width of the grinding face of the head depended upon to give a true cylindrical chamber for the entire depth.

lhile a preferred example of this improved reamer has been described in detail, it will be apparent that the specific construction of the several parts of the device can be varied in design and proportion, and some parts may omitted, without departing from the scope of the invention as indicated by the following claims.

l claim:

l. A cylinder reamer comprising a multipart cylindrical head, spring means coniined between the parts of the head to separate the saine, a retaining member having spaced parallel end portions adapted to be removably engaged with. the outermost members of the head to retain the head parts in assembled relation after these parts have been pressed together against the expansive action of the spring means, and an abrasive covering surrounding the head.

2. A cylinder reamer comprising an expansible cylindrical head divided by two subi; stantiallv parallel planes extending parallel to the axis ot the cylinder into a main central segment and two similar side segments, parallel guide pins extending from the central segment perpendicular to the dividing planes, there being guide openings in the side segments for receiving the pins, expansion springs mounted in the central segment and engaging the two side sements for separating the same, m-eans for rotating the cylinder,

`f and an abrasive strip one end of which is inserted between the central segment and one side segment and clamped to one of the segments by one of the springs and the remainder of the strip wrapped around the cylindrical wall ot the head.

3. A cylinder rcamer comprising an expansible cylindrical head divided by two substantially parallel planes extending parallel to the axis of the cylinder into a main cen- 1 tral segment and two similar side segments,

parallel guide pins extending from the central segment perpendicular to the dividing planes, there being guide openings in the side segments for receiving the pins, expansion springs mounted in the central segment and engaging the two side segments for separating the same, a driving spindle detachably connected with the central segment coaxially of the cylinder, and an abrasive strip wrapped around the cylindrical wall of the head.

t. A cylinder reamer comprising an expansible cylindrical head divided by two substantially parallel planes extending parallel to the axis ot the cylinder into a main central segment and two similar side segments, parallel guides pins extending from the central segment perpendicular to the dividing planes, there being guide openings in the side segments for receiving the pins, expansion springs mounted in the central segment and engaging the two side segments for separating the same, means for rotating the cylinder, a retaining member detachably connected with the two side segments to hold the segments assembled against the action of the springs, and an abrasive strip wrapped around the cylindrical wall of the head.

5. A cylinder reamer comprising an expansible cylindrical head divided by two substantially parallel planes extending parallel to the axis of the cylinder into a main central segment and two similar side segments, parallel guide pins extendingiirom the central segment perpendicular to the dividing planes, there being guide openings in the side segments for receiving the pins, expansion springs mounted in the central segment and engaging the two side segments to separate the saine, a guide stem extending coaxially from one side of the central segment, a coaxial driving spindle removably engaged with the opposite side of the central segment, a retaining member detachably connected with the two side segments to hold the segments assembled against the action of the springs, and an abrasive strip wrapped around the cylindrical wall of the head.

6. A cylinder reamer comprising an expansible cylindrical head divided by two substantially parallel planes extending parallel to the axis of thev cylinder into a main central segment and two similar side segments, parallel guide pins extending from the central segment perpendicular to the dividing planes, there being guide openings in the side segments for receiving the pins, expansion springs mounted in the central segment and engaging the two side segments to separate the same, a guide stem extending coa-xially Jfrom one side of the central segn ent, a guide member consisting of a hollow cylinder in which the stem is journaled and a mit threaded on one end portion of the cylinder, there being an outward y `extendingconical f llt);

surface on the inner end of the nut and an opposed outwardly extending conical surface on the other end of the cylinder, whereby the guide member may be coaxi ally centered within al cylindrical passage, a coaxial driving spindle removably engaged with the opposite side of the central segment of the heath a. detachable retaining member connecting the two side segments to hold the segments assembled against the action of the springs, and an abrasive strip wrapped around the cylindrical wall of the head.

7. A cylinder reamer comprising an expansible cylindrical head divided by two substantially' parallel planes extending parallel to the axis of the cylinder into a main central segment and two similar side segments, parallel guide pins extending from t1 ne central segment perpendicular to the dividing planes, there being guide openings in the side segments for receiving the pins, expansion springs mounted in the central segment and engaging the two side segments to separate the same, a guide stem extending ceaxially from one side ot the central segment, there being a threaded opening formed coaxially in the side of the central segment of the head opposite the guide stem, a driving spindle having` a threaded end portion adapted to be detachably engaged in the opening, a retaining member detachably connected with the two side segments to hold the segments assembled against the expansive action of the springs, and an abrasive strip wrapped around the cylindrical wall of the head.

8. A cylinder reamer comprising an expansible cylindrical head divided by two substantially parallel planes extending parallel to the axis of the cylinder into a main central segment and two similar side segments, parallel guide pins extending from the central segment perpendicular to the dividing` planes, there being guide openings in the side segments for receiving the pins7 expansion springs mounted in the central segment and engaging the two side segments to sepa rate the same, a guide stem extending coaxia-lly from one side oi the central segment, a g 1ide member consisting of a hollow cylinder in which the stem is journaled and a nut threaded on one end portion of the cylinder, there being an outwardly extending conical surface on the inner end of the nut and an opposed outwardly extending conical surtace on the other end of the cylinder, whereby the guide member may be coaxially centered within a cylindrical passage, there being a threaded opening formed coaxiially in the side of the central segment of the head opposite the guide stem, a driving spindle having a threaded end portion adapted to be detachably engaged in the opening, a retaining member detachably connected with the two side segments to hold the segments as sembled against the expansive action of the springs, and an abrasive strip wrapped around the cylindrical wall of the head.

9. A cylinder rearner comprising an expansible cylindrical head divided into a plu rality of segments, springs confined between the segments to separate same, and an expansible strip having one end inserted between two of the segments and clam ed to the segment by one of the springs, t e remainder of the strip being wrapped around the cylindrical wall of the assembled segments.

l0. A cylinder reamer comprising an expansible cylindrical head divided into a plurality of segments, springs confined between the segments to separate same, and an expansible strip having one end inserted between two o'f the segments and secured to one et the segments, the remainder of the strip being wrapped loosely around the cylindri cal wall ot' the assembled segments.

JAMES M. DOLLY. 

